Rotary regenerator assembly having improved sealing means



March 30, 1965 c. P. koLTHoFF, JR 3,175,505

ROTARY REGENERATOR ASSEMBLY HAVING IMPROVED SEALING MEANS Original Filed Feb. 26, 1959 :s Sheets- Sheet 1 R M U H m W m Q GPauZ 21 02 we IMPROVED SEALING MEANS March 30, 1965 c. P. KOLTHOFF, JR

ROTARY REGENERATOR ASSEMBLY HAVI Original Filed Feb. 26, 1959 3 Sheets-Sheet 2 March 30, 1965 c. P. KOLTHOFF, JR 3, 0

ROTARY REGENERATOR ASSEMBLY HAVING IMPROVED SEALING MEANS Original Filed Feb. 26, 1959 3 Sheets-Sheet 3 l R /20 I H m... .1 ////////l United States Patent ration of New Jersey Original application Feb. 26, 1959, Ser. No. 795,689, now Patent No. 3,085,625, dated Apr. 16, 1963. Divided and this application Feb. 11, 1963, Ser. No. 257,708

4 Claims. (Cl. 1659) This invention relates to a heat exchanger and particularly to a rotary regenerator of a type used in combination with gas driven turbines. More specifically the invention relates to an improved sealing arrangement for a rotary regenerator.

This is a division of patent application Serial No. 795,- 689, filed February 26, 1959, now Patent No. 3,085,625 granted April 16, 1963.

The rotary regenerator unit or assembly generally comprises a casing having a regenerator rotatably supported therein. The regenerator generally comprises a cylindrical permeable matrix. The casing is divided into a high pressure chamber and a low pressure chamber through which the permeable regenerator matrix rotates. The high pressure chamber is generally connected to the compressor of a gas turbine and the low pressure chamber is generally connected to the exhaust outlet of the gas turbine. Thus during movement of the regenerator drum or matrix, the matrix is heated in the low pressure chamber by the exhaust gases and is then moved into the high pressure chamber whereupon the compressed air in its travel through the matrix, is preheated prior to its delivery to the combustor of the gas turbine. One of the most significant problems of regenerator design has been the problem of sealing the low pressure chamber from the high pressure chamber in the area of the sealing elements through which the matrix is moved. It is a prime object of this invention to provide an improved regenerator and sealing means having a high effectiveness so as to prevent blow-by at the area of the openings of the high pressure and low pressure chambers through which the regenerator matrix moves.

Another object is to provide an improved sealing arrangement for a rotary regenerator, the said sealing arrangement comprising first and secondary seals in combination with circumferential seals which efficiently seal the various chambers of a rotary regenerator casing through which a regenerator matrix passes.

A more specific object is the provision of an improved regenerator seal having first and second seals which effectively seal the passageways between the low pressure and high pressure chambers of the regenerator casing, the regenerator being movable through said passages.

A still further object is the provision of an improved regenerator seal, the said seal being adapted to effectively seal the passageways between low pressure and high pressure chambers, said seals being arranged to follow in effective sealing arrangements the movement of the regenerator as it is moved within a regenerator casing.

Another object is to provide an improved circumferential seal adapted to effectively seal the upper and lower surfaces of a cylindrical regenerator having a permeable wall construction.

These and other objects will become more readily apparent from a reading of the description when examined in connection with the accompanying sheets of drawings.

In the drawings:

FIGURE 1 is a side elevational view of a gas turbine having a regenrator unit positioned thereon in operative relation;

3,175,695 Patented Mar. 30, 1965 ice FIGURE 2 is an end view of the gas turbine and regenerator unit shown in FIGURE 1, the said view showing a compressor air inlet means;

FIGURE 3 is a plan view of the gas turbine and regenerator shown in FIGURES 1 and 2;

FIGURE 4 is a cross sectional view through a regenerator casing taken along the line 44 of FIGURE 1;

FIGURE 5 is an enlarged side view of a gas turbine and rotary regenerator, portions of the regenerator being shown in section and portions of the gas turbine being broken away to illustrate certain elements of the invention;

FIGURE 6 is an enlarged cross sectional view through a regenerator matrix and upper and lower circumferential seals taken substantially along the line 66 of FIG- URE 4;

FIGURE 7 is a view taken substantially along the line 77 of FIGURE 6;

FIGURE 8 is a cross sectional view taken along the line 8-8 of FIGURE 7;

FIGURE 9 is a cross sectional view taken along the line 9-9 of FIGURE 7; and

FIGURE 10 is a detail view of a circumferential sealing element.

Referring now particularly to FIGURES 1 through 4, a gas turbine is generally designated by the reference character It). The gas turbine It! comprises a gas turbine casing 11 having positioned thereon in superposed relation a regenerator casing 12. The gas turbine 1t comprises a compressor air inlet shroud 13 communicating with a compressor 14 which is suitably mounted for rotation with a shaft 15 in turn connected to a compressor driving turbine 16. The gas turbine 10 is conventional in design including a drive turbine rotor 17 mounted on a shaft 18 within the gas turbine 11. The shaft 18 is provided at its opposite end with a drive pinion 19 which is in mesh with a gear 20 suitably connected to a power take off shaft 21.

The regenerator casing 12 comprises a vertically and circumferentially extending side wall 22, and a top wall 23. The casing 12 also includes a scroll passage or compressor connection or chamber 24, which is in communication with an air chamber provided in the regenerator casing 12.

As best shown in FIGURE 4, a leading seal is designated at 26 and a trailing seal is designated at 27. The casing 12 also includes a bottom wall 28 and a combustor chamber is designated at 29. The combustor chamber 29 is formed by partition or wall 30 extending upwardly from the bottom wall 28 to the top wall 23. The partition or wall 30 also engages and terminates at the leading seal 26 and at the trailing seal 27. An exhaust chamber is designated at 31 within the casing 12. An exhaust outlet chamber of conventional design is designated at 31'. A combustor 32 is suitably mounted within the combustor chamber 29. The said combustor 32 comprising an outer casing 33 and an inner casing 34, and includes a fuel injector 35 and an ignitor 36. Immediately below the combustor 32 there is provided, within the turbine casing 11, a passage 37 which is in communication with the compres sor turbine 16. An exhaust passage is designated at 38, the said exhaust passage being in communiaction with the drive turbine 37.

A regenerator drum is generally designated by the reference character 39 as shown in FIGURES 4 and 5. The regenerator drum 39 comprises an upper wall 40 and a lower Wall 41. A permeable matrix 42 of cylindrical shape is positioned between the upper wall and lower walls 40 and 41. The matrix 42 may be of conventional design which will afford permeability for air and gases to pass therethrough in a radial direction but is not permeable in a circumferential direction as is conventional in the art of rotatable regenerators. The regenerator drum 39 has an outer circumferential wall sur face or wall 41' and an inner circumferential surface or wall 42'. The matrix 42 is positioned to rot-ate on idler rollers 43 and drive roller 44 suitably connected to the bottom wall 28 and top wall 23 of the casing 12. As shown in FIGURE 4,. the drive roller 44 is suitably positioned to rotate the regenerator drum 39, the said drive roller 44, as shown in FIGURE 1, being rotated by means of a regenerator drive arrangement 45 suitably connected to be rotated by the driven parts of the compressor 14, the latter not being shown in detail.

Referring now particularly to FIGURES 5, 6, and 7, the casing 12 is provided with upper and lower circumferential seals 115 and 116. The seal 115 includes aring 117 which is suitably connected to the top wall 23. Similarlya lower ring 118 is connected to the wall 28. The upper ring 117 and the lower ring 118 are respectively provided with annular recesses 119 and 120 as best shown in FIGURE 6. A plurality of graphite sealbl-ocks 121and 122 are supported within the recesses 119 and 120. The graphite seal blocks 121 and 122 comprise individual pieces having a length anywhere from one to six inches, the said seal blocks 121 and 122 being generally of a triangular shape. The seals 121 and 1 22 may be identical, the seals 121 being positioned on topof the matrix 42 and the seals 122 being positioned below the matrix 42. The seals 121 and 122 .are provided at one end with a triangular extension 123 and at its'opposite end with a diagonally extending substantially flat portion 124.. The flat rectangular portion 124 of each seal 121 and 122complements an adjacent triangular undercut portion 125 provided on'each.

seal 121 and 122. Thus as best shown in FIGURE 8 the triangular extension 123 fits into the triangular under cut 125 of the adjacent memberr121. Each of the members 121 and 122 is also provided with a matching face 126 matching the diagonal portion 124 so that when adjacent ends of the members 121 or 122 are placed in assembly with the triangular extension 123 in the undercut 125, the end of the portion 124 and the face 126 are positioned together in substantially adjacent arrangement. Thus in other words, each seal member 1 21 and 122 is provided with a triangular extension 123 at one end a nd :a triangular undercut 125 at its other end including at the said other end'a projecting diagonal fiat portion 124. FIGURE 7 shows the interengagement of the adjacent ends of themembers 121 with the triangular extension 123 in the undercut 125.

Spring-like brackets 127 are suitably connected by means of screws 129 to the upper ring 117 at intervals about the periphery of the ring, the said brackets 127 including a vertical extension 128 which is placed between the diagonal rectangular portion 124 of one member 121 and the diagonal face portion 126 of an adjacent member 121- These brackets 127 serve to position the graphite seals 121 and 122 to prevent their rotation as they engage the upper and lower surfaces 40 and 41 of the rotating regenerator matrix. The brackets 127 are suitably connected to the lower ring 118 in the same manner as they are connected to the upper ring 117 with the exception, of course, that thebrackets 127 .ofthe upper ring 117 face downwardly and the brackets 127 which are connected to the lower ring 118 face upwardly, this latter arrangement not being shown. Spring clips 130 aresuitably connected by means of screws 131 to the rings 11 7 and 118as indicated. The spring clips serve to engage the graphite seals 121a-nd 122 to urge them into engagement with the upper and lower surfaces or walls 40 and 41 of the re'generator drum 39 and surfaces11'9 and 120 of the rings :1-17 and. 118. Thus the clips 130 resiliently urge the graphite seals so that efiective' scaling is obtained. The seals are kept against rotation by means. of the brackets 127, and by virtue of the extensions 123 effective sealing is obtained even 4 though the seals may moverelatively cincumferentially during operation of the regenerator. Referring to FIG- URE 8, the diagonal portions 124 seal against the regenerator at B whereas the triangular extensions 123 seal at C and C. Thus an effective sealing arrangement is provided. I

The operation of the gas turbine is conventional in that air is sucked in through the shroud 13 whence the compressor wheel 14 increases its pressure and forces the air through they scroll passage or compressor connection'24 to: the air chamber 25. The air is forced through the matrix into the combustor chamber 29,

through the combustor whereinthe hot gases under presv sures are forced downwardly through the passage 37 and against the compressor driving turbine 16 against the drive turbine 17. Thus the compressor turbine 16.and drive turbine 17 are rotated in conventional manner. The exhaust from the drive turbine 17 travels at substantially atmospheric pressure through the exhaust passage 38 into the exhaust chamber'31 through the matrix 42 to the exhaust outlet chamber 31 and out through outlets 132.

v The regenerator 39 is provided, as previously stated, for the purpose .of preheating the air at it is delivered to the cornbustor 32. The regenerator drum 39 is rotating and as a portion of the matrix 42 is positioned within the exhaust chamber 31, that portion is heated by means of the exhaust gases passing through the matrix. That same heated portion then passes into the compressed airchamber 25 whereupon the incoming compressed air is forced through the heated matrix whereupon preheating of the said air takes place. This generally is conventional in rotary regenerators. The operation of the seals 115 and 116 will now be described.

The purpose of the seal 26 is, of course, to seal the chamber 25 from the chamber 38 which like the chamber 31, as above described, is an exhaust chamber. Furthermore, the seal 26 seals the combustor chamber29 from the exhaust'chamber 31. The seal 27 performs a similar function. g r

Referring now particularly to. FIGURES .5 and 6 through 10, the circumferential seals 115 and 116 serve to suitably seal the chambers from each other during rotation of the regenerator drum thereby forcing allof the Also as noted in FIGURE 8, by virtue of the recessed portion and the extension 123 of adjacent seals and their mating relation, effective scaling is obtained. atthe point of separation of the adjacent seals 121. .Thus as shown in FIGURE 8, effective sealing is obtained at B and C even though the seals are individual portions. The individual 156318 are easily'replaceable and are capable of adjusting circumferentially to accommodate expansion and contraction which might take place by virtue of the difference in temperature between the air and exhaust chambers. i V

Thus it is obvious that a newjand improved sealing arrangement for rotary regenerators has'bcen disclosed. It must be understood that changes modifications maybe made without departing from the spirit of the invention or the scope thereof as defined inthe appended claims.

What is claimed is: I g a 1.. In a regene'r-at-or having a casing including at least two chambers, a cylindrical regenerator rotatably positioned within said casing, said regenerate: having a permeable matrix including top and bottom walls and inner and 01116 t cumferential walls, one of the chambers of said casing being disposed outwardly from the outer wall and the other chamber being disposed inwardly from the inner wall, first and second circuniferentially extending seals, positioned on said casing and being respectively coextensive with said top and bottom walls, each seal comprising an annular support connected to said casing and projecting toward said top and bottom walls, said supports each including a circumferentially extending recess defined by cir-cumferentially extending vertical and horizontal walls, a plurality of seal elements supported on said ventical walls for sliding movement toward and away from said top and bottom Walls, said seal elements having first sealing surfaces engaging said top and bottom walls and second sealing surface-s engaging said ventical walls, resilient means on said supports engaging said seal elements to urge said sealing surfaces into sealing contact with said vertical walls and said top and bottom walls, said seal elements having undercut portions at an end and projecting tongues at opposite ends, the tongue of one seal element engaging the undercut portion or an adjacent seal element in overlapping arrangement, and means on said supports engaging said seal elements to engage them and secure them against circumferential movement during rotation of said matrix.

2. A regenerator in accordance with claim 1, wherein said seal elements include a plurality of circumferential spaced spring clips connected to said supports and engaging said seal elements.

3. A regenerator in accordance with claim 1, said undercut portion and said tongues including third sealing surface-s engaging said top and bottom walls of said matrix in sealing relation.

4. In a regenerator having a casing including at least two chambers, a cylindrical regenerator rotatably positioned within said casing, said regenerator having a permeable matrix including top and bottom walls and inner and outer circumferential walls, one of the chambers of said casing being disposed outwardly from the outer wall and the other chamber being disposed inwardly from the inner wall, first and second circumferentially extending seals positioned on said casing and being respectively coextensive with said top and bottom walls, each seal comprising a support connected to said casing and projecting toward said top and bottom walls, said supports each in cluding a cireum-ferentially extending recess defined by circumferentially extending horizontal and vertical walls, a plurality of seal elements supported on said vertical walls for sliding movement toward and away from said top and bottom walls, said seal elements having first sealing surfaces engaging said top and bottom walls and second sealing surfaces engaging said vertical walls, resilient means on said supports engaging said seal elements to urge said sealing surfaces into sealing contact with said vertical walls and said top and bottom wmls, said seal elements having under-cut portions at an end and pro jecting tongues at opposite ends, the tongue of one seal element engaging the undercut portion of an adjacent seal element in overlapping arrangement, and means on said supports engaging said seal elements to engage them and secure them against circumferential movement during rotation of said matrix.

References Cited by the Examiner UNITED STATES PATENTS CHARLES SUKALO, Primary Examiner. 

1. IN A REGENERATOR HAVING A CASING INCLUDING AT LEAST TWO CHAMBERS, A CYLINDRICAL REGENERATOR ROTATABLY POSITIONED WITHIN SAID CASING, SAID REGENERATOR HAVING A PERMEABLE MATRIX INLCUING TOP AND BOTTOM WALLS AND INNER AND OUTER CIRCUMFERENTIAL WALLS, ONE OF THE CHAMBERS OF SAID CASING BEING DISPOSED OUTWARDLY FROM THE OUTER WALL AND THE OTHER CHAMBER BEING DISPOSED INWARDLY FROM THE INNER WALL, FIRST AND SECOND CIRCUMFERENTIALLY EXTENDING SEALS, POSITIONED ON SAID CASING AND BEING RESPECTIVELY COEXTENSIVE WITH SAID TOP AND BOTTOM WALLS, EACH SEAL COMPRISING AN ANNULAR SUPPORT CONNECTED TO SAID CASING AND PROJECTING TOWARD SAID TOP AND BOTTOM WALLS, SAID SUPPORTS EACH INCLUDING A CIRCUMFERENTIALLY EXTENDING RECESS DEFINED BY CIRCUMFERENTIALLY EXTENDING VERTICAL AND HORIZONTAL WALLS, A PLURALITY OF SEAL ELEMENTS SUPPORTED ON SAID VERTICAL WALLS FOR SLIDING MOVEMENT TOWARD AND AWAY FROM SAID TOP AND BOTTOM WALLS, SAID SEAL ELEMETNS HAVING FIRST SEALING SURFACES ENGAGING SAID TOP AND BOTTOM WALLS AND SECOND SEALING SURFACES ENGAGING SAID VERTICAL WALLS, RESILIENT MEANS ON SAID SUPPORTS ENGAGING SAID SEAL ELEMENTS TO URGE SAID SEALING SURFACES INTO SEALING CON- 